1. Technical Field
Various embodiments generally relate to a semiconductor apparatus, and, more particularly, to a semiconductor memory apparatus and a method for training a reference voltage.
2. Related Art
A semiconductor apparatus uses various reference voltages to discriminate between logic levels of data or internal signals.
In general, a reference voltage may be set as an intermediate value between a potential defining a logic high level and a potential defining a logic low level.
Reference voltages serve as absolute voltages for determining logic levels of data or internal signals. Therefore, reference voltages should have levels capable of processing data or internal signals without an error.
Recently, in a semiconductor apparatus, a reference voltage training technique for setting the level of a reference voltage by finding, during a booting process, a level range of the reference voltage within which the semiconductor apparatus may normally operate is used.
In a semiconductor apparatus, a reference voltage to be used in discriminating the logic level of data may also be trained during a booting process. A data reference voltage determined through training may serve as a factor for determining the size of a valid data window.